Python Interview Question: Memoize Function Using Closure (supports multiple args + mutable inputs like lists/dicts)

memoize.py

"""
Python Coding Question: Memoize Function Using Closure
======================================================

You are given a function. Write another function called `memoize` that can wrap
any function and cache its result.

If the wrapped function is called again with the same input, it should return
the cached result instead of executing the original function again.

The input can be of any type: integer, string, tuple, list, dictionary, or
multiple arguments.


Requirements
------------
Implement `memoize(fn)` such that:

1. It accepts any function as input.
2. It returns a new function.
3. The new function should cache previous results.
4. If the same arguments are passed again, return the cached value.
5. It should support multiple arguments.
6. It should handle mutable inputs like lists and dictionaries if possible.
"""


def memoize(fn):
    # write your code here
    pass


# Example 1
def add(a, b):
    print("calculating...")
    return a + b


memoized_add = memoize(add)

print(memoized_add(2, 3))  # calculating... 5
print(memoized_add(2, 3))  # 5, should come from cache
print(memoized_add(4, 5))  # calculating... 9


# Example 2
def greet(user):
    print("generating greeting...")
    return f"Hello {user['name']}"


memoized_greet = memoize(greet)

print(memoized_greet({"name": "Suman"}))
print(memoized_greet({"name": "Suman"}))
# should ideally return cached result if input value is same


# Expected Output Behavior
# ------------------------
# calculating...
# 5
# 5
# calculating...
# 9
# generating greeting...
# Hello Suman
# Hello Suman